Apium graveolens is a plant species in the family Apiaceae
The Apiaceae , commonly known as carrot or parsley family, is a group of mostly aromatic plants with hollow stems. The family is large, with more than 3,700 species spread across 434 genera, it is the sixteenth largest family of flowering plants...

 commonly known as celery (var. dulce) or celeriac
Celeriac is also known as celery root, turnip-rooted celery or knob celery. It is a kind of celery, grown as a root vegetable primarily for its large and bulbous hypocotyl rather than for its stem and leaves. The swollen hypocotyl is typically used when it is about 10–12 cm in...

 (var. rapaceum), depending on whether the petiole
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...

s (stalks) or root
In vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...

s are eaten: celery refers to the former and celeriac to the latter. Apium graveolens grows to 1 m tall. The leaves are pinnate to bipinnate leaves with rhombic leaflets 3–6 cm long and 2–4 cm broad.